Fig. 1. Design and characterization of an all-dielectric one-dimensional photonic crystal (1DPC) chip. (a) Diagram of 1DPC chip structure; (b) photograph of the fabricated planar 1DPC chip; (c) transmission spectrum of 1DPC chip; (d) back focal plane image of 1DPC chip; (e) intensity profiles of optical transfer functions along the dashed lines in Fig. 1(d) and the corresponding quadratic fitting curve

Fig. 2. Characterization of topological differentiator. (a) Schematic of interferometric measurement lightpath for detecting topological charges; (b) interference pattern of vortex light field

Fig. 3. Modulation effect of differential device on the front focal plane. (a) Schematic of experimental setup for front focal plane imaging; (b) bright field image of the 1951 USAF resolution chart; (c) differential image of the 1951 USAF resolution chart, the inserted image is the enlarged image of an edge

Fig. 4. Bright field image and differential image of onion epidermal cells. (a) Bright field image; (b) differential image